Nanofluids have become the subject of theoretical and experimental researches over the few decades due to their enhanced heat transfer performance. In this study, thermal conductivity of copper argon nanofluids is determined through MD simulation. Different types of nanoparticles based on shape was used to make nanofluids. Role of different shape of nanoparticles such as cylindrical, cubical and spherical was disused. Green Kubo method is employed to determine the thermal conductivity of the nanofluids. Result shows that, for volume fraction 3% and 86 K system temperature, thermal conductivity enhancement of nanofluid containing spherical, cubical and cylindrical shape is 15%, 40% and 50% respectively compared with that of base fluid. Thermal conductivity enhancement of nanofluid for spherical particle at 86 K, 94 K and 102 K is 15%, 30% and 40% respectively while for volume fraction 3%, 6% and 9%, the enhancement is 15%, 35% and 45% respectively. The mechanism of increased heat transfer performance for different shape of the nanoparticles is discussed in this paper.